The present invention addresses the problem of providing a method for producing nickel microparticles in which the ratio of crystallite's diameter to the particle diameter of the nickel microparticles is controlled. At least two types of fluids to be processed are used, including a nickel compound fluid in which a nickel compound is dissolved in a solvent, and a reducing agent fluid in which a reducing agent is dissolved in a solvent. Sulfate ions are included in the nickel compound fluid, and polyol is included in the nickel compound fluid and/or the reducing agent fluid. The fluid to be processed is mixed in a thin film fluid formed between at least two processing surfaces (1, 2), at least one of which rotates relative to the other, and which are disposed facing each other and capable of approaching and separating from each other, and nickel microparticles are precipitated. The present invention is characterized in that at this time, the ratio (d/D) of crystallite's diameter (d) to the particle diameter (D) of the nickel microparticle is controlled by controlling the pH of the nickel compound fluid introduced between the processing surfaces (1, 2) and the molar ratio of sulfate ions with respect to nickel in the nickel compound fluid.

Provided are processes for preparing a thermodynamically stable PtBi.sub.2 alloy nanoparticle. In certain aspects, the process comprises preparing an aqueous mixture, with the aqueous mixture comprising: an inorganic compound comprising SnCl.sub.2; an inorganic compound comprising Bi; and HCl. The process further comprises adding PtCl.sub.4 to the mixture. The process results in the spontaneous reduction of Bi and Pt. Excess SnCl.sub.2 is adsorbed as a ligand at the surface of the PtB.sub.2 alloy nanoparticle, which serves to stabilize the nanoparticle. Another aspect provides a thermodynamically stable PtBi.sub.2 nanoparticle. The nanoparticle comprises a core comprising a PtBi.sub.2 alloy. The nanoparticle further comprises a shell at least partially encapsulating the core, with the shell comprising stannous chloride. The thermodynamically stable PtB.sub.2 nanoparticle has a negative charge.

A magnetic core includes a metal magnetic powder, which has a large size powder, an intermediate size powder, and a small size powder. A particle size of the large size powder is 10 μm or more and 60 μm or less. A particle size of the intermediate size powder is 2.0 μm or more and less than 10 μm. A particle size of the small size powder is 0.1 μm or more and less than 2.0 μm. The large size powder, the intermediate size powder, and the small size powder have an insulation coating. When A1 represents an average insulation coating thickness of the large size powder, A2 represents an average insulation coating thickness of the intermediate size powder, A3 represents an average insulation coating thickness of the small size powder, A3 is 30 nm or more and 100 nm or less, A3/A1≥1.3, and A3/A2≥1.0.

Metal powder particles for use in additive manufacturing are made by removing material from the surface of the particles using wet chemical etching to create a nanoscale texturing of the surface, increasing absorptivity by the metal powder particles of incident laser light and maintaining flowability. The nanoscale texturing has sub-wavelength features at laser wavelengths in the range 800-1100 nm. The particles are substantially spherical and have mean diameters in the range 10-70 μm.

Metal powder particles for use in additive manufacturing are made by removing material from the surface of the particles using wet chemical etching to create a nanoscale texturing of the surface, increasing absorptivity by the metal powder particles of incident laser light and maintaining flowability. The nanoscale texturing has sub-wavelength features at laser wavelengths in the range 800-1100 nm. The particles are substantially spherical and have mean diameters in the range 10-70 μm.

Metal powder particles for use in additive manufacturing are made by removing material from the surface of the particles using wet chemical etching to create a nanoscale texturing of the surface, increasing absorptivity by the metal powder particles of incident laser light and maintaining flowability. The nanoscale texturing has sub-wavelength features at laser wavelengths in the range 800-1100 nm. The particles are substantially spherical and have mean diameters in the range 10-70 μm.

Processes for preparing stabilized metal-containing nanoparticles comprising silver and/or a silver alloy composite by reacting a silver compound with a reducing agent comprising a hydrazine compound at a temperature between about 20° C. and about 60° C. The reaction being carried out by incrementally adding the silver compound or a mixture of the silver compound and a stabilizer to a solution comprising the reducing agent, a stabilizer, and a solvent. Conductive ink compositions containing stabilized metal-containing nanoparticles prepared by such processes.

A soft magnetic nanoparticle comprising an iron aluminide nanoalloy of the DO.sub.3 phase as a core encapsulated in an inert shell made of alumina.

The present invention includes composition and methods for the fabrication of very-high-aspect-ratio structures from metallic glasses. The present invention provides a method for nondestructive demolding of templates after thermoplastic molding of metallic glass features.

A method for producing metal nanowire of small diameter and long length. In the method for producing a metal nanowire, a first solution containing an ionic derivative and a polyol as a solvent are kept at 80-200° C., and a second solution containing a metal salt and a polyol as a solvent is supplied into the first solution so that the ratio between the number of moles of metal atoms in the metal salt supplied in one minute and the total number of moles of halogen atoms in the ionic derivative in the first solution (the number of moles of metal atoms in the metal salt supplied in one minute/the total number of moles of halogen atoms in the ionic derivative) is less than 10. It is preferable that the ionic derivative is a quaternary ammonium halide and the metal salt is silver nitrate.